JP2020504826A - Image sensor with polarization sensitivity - Google Patents

Abstract

The device includes a first multiple element image sensor, a second multiple element image sensor, and a polarizing layer positioned between the first multiple element image sensor and the second multiple element image sensor. A portion of the light having a first polarization state incident on the device along a first direction is transmitted through the first image sensor, transmitted through the polarizing layer, and transmitted by the second image sensor. Light detected and incident on the device along the first direction and having a second polarization state orthogonal to the first polarization state is transmitted through the first image sensor and blocked by the polarizing layer. . [Selection diagram] FIG. 1A

Description

  The present disclosure relates generally to image sensors.

  Most conventional image sensors, such as those used in digital cameras, are insensitive to the polarization of the detected light. For applications where polarization sensitivity is desired, typically an absorbing or reflective polarizer is placed in the path of the incident light. This results in about a 50% reduction in light that would otherwise be detected by the sensor for unpolarized incident light. This is because one of the incident polarization states is substantially either absorbed or reflected by the polarizer.

  The present disclosure features an image sensor that includes a pair of sensors, one stacked on top of the other, with a polarizing layer between them. The upper sensor is partially transparent to incident light. Thus, all signals from the upper sensor include a component that is insensitive to the state of polarization and proportional to the intensity of the incident light. Also, the upper sensor transmits a certain fraction of the incident light insensitively to the polarization state. The transmitted light enters the polarizing layer. If the polarizer is a reflective polarizer, most of the rejected polarization states will be reflected back to the upper sensor, but most of the transmitted polarization states will be transmitted to the lower sensor. Thus, for a reflective polarizer, the upper sensor signal also contains a component attributable to the amount of incident light that is composed of the blocked polarization state. Similarly, the lower sensor signal is fully ascribed to the pass state polarization and thus indicates the amount of pass state polarization in the incident light. If an absorptive polarizer is used, the signal from the upper sensor will not include any additional blocked state components. For a properly calibrated system, the ratio of pass state polarization to blocked state polarization at each pixel may be determined by comparing the signal of each upper sensor pixel to the corresponding lower sensor pixel signal. Further, since the sensor detects both pass state light and block state light without discarding all of one polarization state, the S / N reduces the disclosed sensor as compared to conventional arrangements. Overall improvement by use.

  In general, in a first aspect, the present invention provides a method for positioning a first multi-element image sensor, a second multi-element image sensor, and a first multi-element image sensor and a second multi-element image sensor. And a polarizing layer. A portion of the light having a first polarization state incident on the device along a first direction is transmitted through the first image sensor, transmitted through the polarizing layer, and transmitted by the second image sensor. Light detected and incident on the device along the first direction and having a second polarization state orthogonal to the first polarization state is transmitted through the first image sensor and blocked by the polarizing layer. .

  Embodiments of this device can include one or more of the following features. For example, the polarizing layer can substantially reflect light having a second polarization state, and at least a portion of the blocked light is detected by the first image sensor.

  Each element of the first multi-element image sensor may be registered with a corresponding element of the second multi-element image sensor.

  Each element of the first multi-element image sensor may be laterally offset with respect to a corresponding element of the second multi-element image sensor.

  One or both of the first and second multi-element image sensors may be a complementary metal oxide semiconductor (CMOS) array, a photodiode array, or a charge-coupled device (CCD) array. it can.

  The polarizing layer can be a linear polarizer having a single pass axis direction. The polarizing layer can be a circular polarizer. In some embodiments, the polarizing layer is composed of a plurality of polarizing elements, with adjacent polarizing elements having differently oriented pass axes. Each element of the polarizing layer can correspond to an element of the first multi-element image sensor. The polarizing layer and the corresponding elements and elements of the first multi-element image sensor can be registered with one another. Each element of the polarizing layer can correspond to an element of the second multi-element image sensor. The polarizing layer and corresponding elements and elements of the second multi-element image sensor may be registered with each other and with corresponding elements of the first multi-element image sensor.

  The polarizing layer can include a reflective polarizer and / or an absorbing polarizer.

  The polarizing layer can include a polarizing metal grating, a dielectric grating, or an air gap grating.

  In some embodiments, the device can include a color filter layer that includes an array of color filter elements.

  In another aspect, the invention features a system that includes the device and an electronic processing module in communication with the device. In operation, the device detects the incident light and sends a signal to the electronic processing module, which determines information about the intensity of the incident light and information about the polarization of the incident light based on the signal. The information regarding the polarization of the incident light may include a relative intensity between the incident light polarized in the first direction and the incident light polarized in a second direction orthogonal to the first direction. Information regarding intensity and polarization may be determined for each of a plurality of locations across the device.

  In some embodiments, the system can include one or more optical elements positioned to focus incident light on the device. One or more optical elements can image light onto the device.

  In a further aspect, the invention features a camera or spectroscopic detector that includes the system.

  Sensors with polarization sensitivity may be useful in many imaging or spectroscopy applications where polarization sensitivity is important. Further, the disclosed device architecture is achievable using wafer processing techniques, allowing for large scale manufacturing in a compact, integrated form factor and economical form, e.g., suitable for cell phone cameras To

  The details of one or more embodiments of the presently disclosed subject matter are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will be apparent from the description, drawings, and claims.

1 is a perspective view illustrating an embodiment of a sensor having polarization sensitivity. FIG. 1B is an exploded cross-sectional view showing a single element of the sensor having polarization sensitivity shown in FIG. 1A. It is a top view which shows the polarizer array of the sensor which has polarization sensitivity. FIG. 9 is a perspective view showing a part of another embodiment of a sensor having polarization sensitivity. FIG. 9 is an exploded perspective view showing a further embodiment of a sensor having polarization sensitivity. FIG. 1 is a schematic diagram illustrating an imaging system including a sensor having polarization sensitivity. FIG. 2 is a schematic diagram illustrating an embodiment of an electronic processing module.

  Like reference numbers and designations in the various figures indicate like elements.

  Referring to FIG. 1A, a polarization-sensitive image sensor 100 includes three layers stacked on top of each other: a first sensor layer 110, a second sensor layer 130, and first and second sensor layers. And a polarizer layer 120 between the two sensor layers. All of the elements are glued together to provide a compact integrated package. As described below, the image sensor 100 is configured to detect both intensity information and polarization information for the light field at different locations on the sensor. Here, light refers to electromagnetic radiation over the operating wavelength range of the sensor. This range can be, for example, the ultraviolet wavelength range (eg, 200 nm to 400 nm), the visible wavelength range (eg, 400 nm to 700 nm), or the infrared wavelength range (eg, 700 nm to 1200 nm).

  The Cartesian axis is shown in FIG. 1A for ease of reference. In this regard, object thickness refers to the dimension of the object measured along the z-axis. The side area of the object refers to the area of the object in the xy plane. "Up" and "down" refer to the + z and -z directions, respectively. For example, the upper surface of sensor 100 refers to the surface facing in the + z direction, and the lower surface refers to the opposing surface. Sensor layer 110 is sometimes referred to below as the upper sensor layer, and sensor layer 130 is correspondingly the lower sensor layer.

  Upper sensor layer 110 and lower sensor layer 130 each include an array of sensor elements. As shown, upper sensor layer 110 includes a 3 × 5 array of individual sensor elements 110a-110o. The lower sensor layer 130 includes a similar 3x5 array of individual sensor elements 130a-130o. Each sensor element of the upper sensor layer has the same lateral dimension as the corresponding sensor element of the lower sensor layer and is registered therewith.

  In general, the upper sensor layer 110 and the lower sensor layer 130 are active pixel sensor arrays composed of integrated circuits that include an array of pixel sensors, each pixel sensor including a photodetector and an active amplifier. Common active pixel sensor technologies that can be used include complementary metal oxide semiconductor (CMOS) sensor technology and charge coupled device (CCD) sensor technology.

  The sensor array is shown as having a relatively small number of pixel sensors for illustrative purposes. More generally, much larger numbers of pixels are common. For example, each array can include sensors up to millions of pixels (eg, up to 20M, 1MP or more, 4MP or more, 8MP or more, 10MP or more, 12MP or more, 15MP or more).

  In general, the lower sensor layer can have an architecture similar to conventional active pixel sensor arrays, such as those commonly used in digital cameras. On the other hand, the upper sensor layer absorbs only a portion of the incident light (and subsequently produces photocarriers that contribute to the detection signal), but transmits a significant amount of the incident light. For example, each sensor element in the upper sensor layer may have about 10% or more (eg, up to 80%, such as 20% or more, 30% or more, 40% or more, 50% or more, 60% or more) of light incident perpendicular to it. , 70% or more).

  Various architectures that provide both light detection and light transmission are possible. For example, in some embodiments, each sensor includes a semiconductor layer that generates photocarriers upon interaction with incident photons of appropriate energy. These regions can be designed to fill only a fraction of the available aperture of each sensor element, allowing the transmission of photons incident on other parts of the sensor. In this case, for each pixel, the polarizer must be at least as large as the aperture through which the upper sensor layer transmits light. Alternatively or additionally, the layer generating the photocarriers can be sufficiently thin to absorb only a fraction of the incident photons of the appropriate energy. As a further alternative, in some embodiments, the upper sensor can use a semiconductor material that has a larger bandgap and thus has less absorption than the lower sensor.

  Although not shown in FIG. 1A, generally, adjacent elements in the same layer of a sensor described herein can be separated by, for example, light absorbing and / or passivating materials.

  Generally, the polarizer layer 120 includes a planar polarizing element, such as a polarizing metal grating. Polarized metal gratings, also called wire grid polarizers, are composed of narrow, spaced parallel metal strips. Commonly used metals are aluminum and gold, but other metals can be used. Typically, the strips are periodically spaced and have a shorter period than the operating wavelength of the polarization sensitive image sensor 100. For example, if the operating wavelength is in the visible portion of the spectrum, the grating period can be about 200 nm or less (eg, 150 nm or less, 100 nm or less, 80 nm or less, 50 nm or less).

  For normally incident light, a polarizing metal grid substantially transmits linearly polarized light having an electric field perpendicular to the grid lines, while substantially reflecting linearly polarized light having an electric field parallel to the grid lines. Act as a polarizer.

Referring also to FIG. 1B, the operation of the sensor 100 refers to a single sensor pixel composed of the sensor element 110a, the sensor element 130a, and the portion of the polarizer layer 120 adjacent to these sensor elements. I will explain. The vertically incident light propagating in the −z direction is incident on the upper surface of the sensor element 110a. For light composed of both s- and p-polarized light, a percentage of the light in each polarization state is absorbed by sensor element 110a and contributes to the signal from that element. Here, referring to FIG. 1B, s-polarized light refers to plane-polarized light whose electric field vector is parallel to the y direction, and p-polarized light refers to plane-polarized light whose electric field vector is parallel to the x direction. More generally, s-polarization refers to plane-polarized light whose electric field vector is perpendicular to the plane of incidence defined by the direction of incidence and surface normal, and p-polarization refers to orthogonal plane polarization. The grid lines extend along the x-direction, such that p-polarized light is substantially reflected while s-polarized light is substantially transmitted. In each case, assuming that the upper sensor element 110a is equally sensitive to both polarization states, a percentage t of light in each polarization state will be transmitted through the lower surface of the sensor, where Light enters the polarizer layer 120. This is the percentage of incident light of each polarization state (1-t) is absorbed by the sensor 110a, is converted into light carrier means to contribute to the detection signal V ₁₁₀ from the sensor 110a.

  The polarizer layer 120 transmits substantially all (eg, 95% or more, 98% or more, 99% or more) incident s-polarized light, and substantially all (eg, 95% or more, 98% or more, 99% or more). % Or more) is arranged to reflect p-polarized light.

The transmitted s-polarized light enters the sensor element 130a, where it is absorbed and produces a signal related to (eg, proportional to) its intensity at the sensor. Thus, for simplicity, if we consider the polarizer layer 120 to be a perfect polarizer and ignore Fresnel reflections between the layers, the detection signal V ₁₃₀ from the sensor element 130a will be: It is related to (eg, proportional to) the intensity S of the s-polarized light incident on the sensor pixel.
V ₁₃₀ @tS

The p-polarized light reflected by the polarizer layer 120 returns to the sensor element 110a, where a portion is absorbed and further contributes to the signal produced by the sensor element, another portion is transmitted and exits the sensor 100 as reflected light. . Again, assuming a perfect polarizer, with respect to the intensity P of p-polarized light initially incident on the sensor pixel, this implies that the quantity t · P is incident on the sensor 110a and that the same fraction of this light (1-t) means that further contribute to the signal _{V 110.} Thus, with respect to this idealization, the signal from the upper sensor element 110 can be expressed as:
V ₁₁₀ = (1−t) · [(1 + t) · P + S]

Thus, based on the signals V ₁₁₀ and V ₁₃₀ from the upper and lower sensor elements, it is possible to determine values for both P and S, assuming that the transmission property t of the upper sensor pixel is known. It is. Thus, each sensor pixel can provide a value of P, a value of S, and an intensity (I = P + S).

  The transmission property t and other properties of the upper sensor pixel (eg, the transmission and reflection properties of the polarizer layer and / or the detection efficiency of the sensor layer 130) can be determined by appropriate calibration of each layer. For example, the properties of each layer can be determined independently under controlled conditions, and the performance of each layer in the final sensor can be calculated from the known performance of each constituent layer. Alternatively or additionally, the sensor can be calibrated using known lighting conditions before deployment in its end use application.

  Other types of linear polarizers can be used. Generally, any element having polarization dependent transmission properties that can be integrated into the sensor between the upper and lower sensor layers, including both reflective and absorbing polarizers, can be used. . For example, a dielectric lattice, an air gap lattice, or other structures such as photonic crystals, quasi-periodic structures, or unidirectionally random structures can be used. In some embodiments, a stained-polymer grating, such as an iodine-stained PVA thin film, can be used. Such thin films are commonly used as linear polarizers in liquid crystal displays.

  In some embodiments, a circular polarizer can be used. For example, the polarizing layer can be formed from a chiral liquid crystal polymer arranged to reflect one handed circularly polarized light while transmitting light having an orthogonal polarization state.

  In the foregoing embodiment, the polarizer layer 120 is a uniform layer having the same pass axis for all sensor pixels. However, patterned polarizers are also possible. For example, referring to FIG. 2, the polarizer layer 200 includes an array of polarizing elements 210, 220, 230, and 240 arranged in four groups. Each of these elements has a differently oriented pass axis than the others. Specifically, element 210 has its pass axis aligned in parallel in the y direction, element 220 is parallel to the x direction, element 230 is at 45 ° to the x axis (measured counterclockwise), 240 are aligned at 135 °. Each polarizing element is registered with corresponding sensor elements in the upper and lower sensor layers. Thus, for each group of four sensor pixels, each pair of signals provides information about the polarization intensity in different directions.

  Further, the sensor elements in the upper and lower sensors of sensor 100 are the same size and the sensors have the same number of pixels, but other embodiments are possible. For example, the number of pixels of the two sensors can be different. In some embodiments, the upper sensor has a lower resolution than the lower pixel, allowing each pixel to have a larger aperture and increasing light transmission to the polarizer layer and the lower sensor. .

  Within the sensor 100, the sensor elements of the upper sensor array are registered with corresponding sensor elements in the lower sensor array, but this is not necessarily the case. In some embodiments, one or both of the sensor layers can feature elements that are laterally offset with respect to adjacent sensor layers. For example, referring to FIG. 3, a sensor (partially shown) includes an upper sensor layer 310, a polarizer layer 320, and a lower sensor layer 330. Upper sensor layer 310 includes transmission sensor elements 310a, 310b, and 310c. The lower sensor layer includes sensor elements 330a, 330b, and 330c, which are laterally offset in the x-direction with respect to sensors 310a, 310b, and 310c, respectively. In contrast, the upper and lower sensor elements in sensor 100 are registered with each other, dividing the sensor into an array of tiled sensor pixels. On the other hand, within the sensor 300, the result is that a sensor element in the lower sensor layer detects light transmitted by a plurality of pixels in the upper sensor layer. In general, the amount of offset can vary. In some embodiments, the lateral offset can be half the pixel width. Further, in some embodiments, pixels are offset in both the x and y directions.

  An image sensor having polarization sensitivity can include other components in addition to the three layers described above. For example, referring to FIG. 4, the sensor 400 includes a color filter layer 440 in addition to an upper sensor layer 410, a polarizer layer 420, and a lower polarizer layer 430. The color filter layer includes tiled color filter elements 440A, 440B, and 440C, each having different spectral transmission properties. For example, for a sensor configured for operation in the visible portion of the spectrum, the three filter elements may transmit red, green, and blue light, or cyan, magenta, and yellow light, respectively. it can. More generally, the filter element may be configured to transmit other spectral bands as desired, such as narrow bands (eg, having a full width at half maximum of 50 nm or less, eg, 10 nm, 20 nm, 30 nm, 40 nm). In some embodiments, the color filter elements can be configured to transmit different wavelength bands in the infrared spectrum. The color filter element can be an absorbing color filter, such as those used in liquid crystal displays. Reflective color filters (eg, dichroic mirrors) are also possible.

  Each color filter element in layer 440 is registered with four corresponding sensor pixels. Specifically, color filter element 440A is registered with partial transmission sensor elements 410a, 410b, 410c, and 410d. Color filter elements 440B and 440C are similarly registered with corresponding partial transmission sensor elements. Partially transmissive sensor elements 410a, 410b, 410c, and 410d are registered with polarizer elements 420a, 420b, 420c, and 420d, respectively, and polarizer elements 420a, 420b, 420c, and 420d, respectively, within sensor layer 430. Registered with sensor elements 430a, 430b, 430c, and 430d.

  In operation, light first enters the color filter layer 440, which spectrally filters the light and preferentially transmits different spectral components through each type of filter. Accordingly, light incident on the transmission sensor elements 410a, 410b, 410c, and 410d has different spectral components as compared to light incident on other elements of the layer 410 shown in FIG. The same applies to additional layers of the sensor 400, the result being that the sensor provides information about the spectral components of the incident intensity pattern, in addition to polarization and spatial intensity information.

  Although the sensor 400 is shown as including three different color filter elements, more generally, the color filter layer 440 may include any number of different filter elements (eg, 10 or 12). (E.g., four or more types, five or more types, six or more types), such as different filter types. Further, with respect to the previously described sensors, only a small number of elements are shown, and in general, a sensor can include a much larger number of sensor pixels than the twelve shown in FIG.

  Instead of or in addition to the color filter layer, the sensor may include other components such as birefringent layers (eg, quarter wave plates, half wave plates), passivation layers, anti-reflective coatings, and / or optical hard coats. May be included. In some embodiments, the sensor can include a microlens array that couples light to the pixels, for example, to achieve more surface normal incidence. For example, a microlens array having a microlens registered with each pixel can be provided on the top surface of the sensor.

  Alternatively or additionally, in some embodiments, a quarter wave retarder is included adjacent to the polarizing layer to convert transmitted linearly polarized light to circularly polarized light. In other words, the combination of the combined linear polarizer and quarter-wave plate operates as a circular polarizer for pass-state polarization.

  In general, the polarization sensitive image sensors described above can be manufactured using techniques commonly used in semiconductor device manufacturing, specifically wafer processing techniques. For example, component parts of an image sensor having polarization sensitivity can be formed by sequentially depositing layers of material on a substrate layer and patterning each layer as needed. Layer deposition is performed using a variety of techniques, depending on the nature of the layer to be formed (eg, material, thickness, crystallinity, etc.) and the nature of the underlying surface on which the layer is formed. Can be done. Exemplary deposition techniques include physical vapor deposition (PVD), chemical vapor deposition (CVD), electrochemical deposition (ECD), molecular beam epitaxy (MBE), and atomic layer deposition (ALD) .

  Layer patterning is commonly performed using lithographic techniques, in which a pattern is transferred to a resist layer and a subsequent etch step transfers the pattern from the resist layer to a layer of material above or below. I do. Initial patterning of the resist layer may be performed using, for example, photolithography or imprint lithography. Wet etching, dry etching, and / or plasma etching can be used to remove material. A polishing process (eg, chemical mechanical polishing) can be used to planarize the exposed surface.

In some cases, a lower sensor is formed on the substrate, a polarizing layer is then formed on the lower sensor, and finally, an upper sensor is formed on the polarizing layer. A passivation layer (eg, formed from SiO ₂ or some other dielectric material) may be formed between each active layer. The passivation layer can be planarized to provide a subsequent active layer with a planar surface formed thereon.

  Alternatively, each sensor may be formed on a separate substrate during a separate manufacturing process, and the polarizing layer may be formed on one of the sensors. The two components are then glued together in a subsequent step to provide a polarization-sensitive image sensor. Alternatively or additionally, each active layer may be formed separately and then subsequently adhered to the corresponding spacer layer. Such an approach may also be desirable where different components are manufactured by different vendors.

  Wafer processing techniques can also be used to form multiple devices on a single wafer, which is subsequently diced to create individual sensor or component layers.

  Polarization sensitive image sensors can be further packaged to provide robust components that can be easily integrated into larger systems, for example by integration into a printed circuit board. Chip packaging techniques conventionally used to package integrated circuits, sensor arrays, LEDs, and diode lasers can be used.

  In general, polarization-sensitive image sensors can be used in various applications where information about the polarization distribution of the light field may be useful. For example, an image sensor having polarization sensitivity may be used in imaging applications where polarization sensitivity is desired. An example of a light sensing system using an image sensor having polarization sensitivity is shown in FIG. Specifically, light sensing system 500 includes a polarization sensitive sensor 510 and focusing optics 530. Sensor 510 is in communication with electronic processing module 520. In operation, the focusing optics image light onto the top surface of the sensor 510, which detects the focused light and sends a corresponding signal to the electronic processing module 520. The electronic processing module analyzes the signal to determine light field intensity information collected on the sensor and also information about the light field polarization distribution.

  The light sensing system 500 is typically part of a larger system, such as a camera (eg, a consumer camera such as a DLSR or cell phone camera). In some embodiments, the light sensing system is part of a machine vision system where information regarding the polarization distribution of the detected image is desired.

  Alternatively or additionally, non-imaging applications are also possible. For example, in some embodiments, polarization-sensitive image sensors are used, for example, in spectral applications where incoming light is split into its component wavelengths, each of which is directed to a different area of the sensor. You. The sensor then provides information on the state of polarization at each wavelength (or band of wavelengths) in addition to the intensity.

  In some embodiments, polarization sensitive image sensors may be used in surface inspection applications. For example, a sensor can be used in combination with a polarized light source to determine whether a surface provides specular or diffuse reflection (specular surfaces preserve more polarization in reflection, but The surface has a depolarizing effect). This may be used, for example, in a manufacturing environment or other instances where automated surface inspection may be required.

  Some aspects of the polarization-sensitive sensors and systems including these sensors described herein include in digital electronic circuitry or include the structures disclosed herein and their structural equivalents. It may be implemented in computer software, firmware, or hardware, or in one or more combinations thereof. For example, in some embodiments, the electronic processing module 520 is implemented using digital electronics or in computer software, firmware, or hardware, or in one or more combinations thereof. Can be done.

  The term “electronic processing module” is used to refer to any and all components for processing data and / or controlling signal generation, including, for example, a programmable processor, a computer, a system-on-a-chip, or a combination thereof. Includes types of equipment, devices, and machines. The electronic processing module may include special purpose logic circuitry, such as an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit). The electronic processing module is, in addition to the hardware, the code that creates the execution environment of the computer program in question, for example, processor firmware, protocol stacks, database management systems, operating systems, cross-platform runtime environments, virtual machines , Or one or more of them. Electronic processing modules and execution environments can implement a variety of different computing model infrastructures, such as web services, distributed computing, and grid computing infrastructures.

  A computer program (also referred to as a program, software, software application, script, or code) may be written in any form of programming language, including a compiled or interpreted language, a declarative language, or a procedural language. . A computer program may, but need not, correspond to a file in a file system. The program may be part of a file holding other programs or data (eg, one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or It may be stored in multiple coordinated files (eg, a file that stores one or more modules, sub-programs, or portions of code). The computer programs may be deployed to be executed on one computer or on multiple computers located at one location or distributed across multiple locations and interconnected by a communication network.

  Some of the processes described above are performed by one or more programmable processors executing one or more computer programs to perform actions by operating on input data and generating output. obtain. The processes and logic flows may also be performed by special purpose logic circuits, such as FPGAs (Field Programmable Gate Arrays) or ASICs (Application Specific Integrated Circuits), and the devices may also be implemented as these special purpose logic circuits .

  Processors suitable for the execution of a computer program include, for example, both general and special purpose microprocessors, as well as processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The computer includes a processor that performs actions in accordance with the instructions, and one or more memory devices that store the instructions and data. The computer also includes one or more mass storage devices for storing data, for example, magnetic, magneto-optical, or optical disks, or for receiving and transferring data thereto, or both. May be operably coupled. However, the computer need not have such a device. Devices suitable for storing computer program instructions and data include, for example, semiconductor memory devices (eg, EPROMs, EEPROMs, flash memory devices, and others), magnetic disks (eg, internal hard disks, removable disks). And other), all forms of non-volatile memory, media, and memory devices, including magneto-optical disks, CD ROM disks, and DVD-ROM disks. The processor and the memory may be supplemented by, or incorporated in, special purpose logic circuitry.

  In order to provide interaction with the user, operations include a display device (eg, a monitor or another type of display device) that displays information to the user, and a keyboard and pointing device by which the user can provide input to the computer. May be implemented on a computer having a device (eg, a mouse, trackball, tablet, touch-sensitive screen, or another type of pointing device). Other types of devices may also be used to provide interaction with the user, for example, the feedback provided to the user may be any form of sensory feedback, such as visual, audible, or tactile feedback And input from the user may be received in any form, including acoustic, audio, or tactile input. Further, the computer sends the document to and receives the document from the device used by the user, for example, by sending the web page to a web browser on the user's client device in response to a request received from the web browser. Can be sent to interact with the user.

  The electronic processing module can include a single computing device or multiple computers operating in close proximity or generally remotely from each other and typically interacting via a communication network. Examples of communication networks include local area networks (“LANs”) and wide area networks (“WANs”), internetworks (eg, the Internet), networks including satellite links, and peer-to-peer networks (eg, ad hoc networks). Peer-to-peer networks). The relationship between the client and the server may be created by computer programs running on the respective computers and having a client-server relationship with each other.

  FIG. 6 illustrates an example electronic processing module 600 that includes a processor 610, a memory 620, a storage device 630, and an input / output device 640. Each of components 610, 620, 630, and 640 may be interconnected, for example, by system bus 650. Processor 610 can process the instructions for execution in module 600. In some implementations, processor 610 is a single-threaded processor, a multi-threaded processor, or another type of processor. Processor 610 may process instructions stored in memory 620 or on storage device 630. Memory 620 and storage device 630 can store information within system 600.

  The input / output device 640 provides an input / output operation to the module 600. In some implementations, the input / output device 640 is a network interface device, eg, an Ethernet card, a serial communication device, eg, an RS-232 port, and / or a wireless interface device, eg, an 802.11 card, 3G wireless. -It may include one or more of a modem, a 4G wireless modem, etc. In some implementations, the input / output devices may include driver devices configured to receive input data and send output data to other input / output devices, for example, keyboards, printers, and display devices 660. it can. In some implementations, mobile computing devices, mobile communication devices such as smartphones or tablet computers, and other devices can be used.

  A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Therefore, other embodiments are within the scope of the following claims.

Claims (23)

A first multi-element image sensor;
A second multi-element image sensor;
A polarizing layer positioned between the first and second multi-element image sensors, wherein the light is incident on the device along a first direction. A portion having a first polarization state is transmitted through the first image sensor, transmitted through the polarizing layer, and detected by the second image sensor;
Light incident on the device along the first direction and having a second polarization state orthogonal to the first polarization state is transmitted through the first image sensor and blocked by the polarizing layer. Device.   2. The method of claim 1, wherein the polarizing layer substantially reflects the light having the second polarization state, and at least a portion of the blocked light is detected by the first image sensor. 3. device.   The device of claim 1, wherein each element of the first multi-element image sensor is registered with a corresponding element of the second multi-element image sensor.   The device of claim 1, wherein each element of the first multi-element image sensor is laterally offset with respect to a corresponding element of the second multi-element image sensor.   One or both of the first and second multi-element image sensors are complementary metal oxide semiconductor (CMOS) arrays, photodiode arrays, or charge-coupled device (CCD) arrays. The device of claim 1.   The device of claim 1, wherein the polarizing layer is a linear polarizer having a single pass axis direction.   The device according to claim 1, wherein the polarizing layer is a circular polarizer.   The device of claim 1, wherein the polarizing layer includes a plurality of polarizing elements, wherein adjacent polarizing elements have differently oriented pass axes.   9. The device of claim 8, wherein each element of the polarizing layer corresponds to an element of the first multi-element image sensor.   10. The device of claim 9, wherein the corresponding elements and elements of the polarizing layer and the first multi-element image sensor are registered with one another.   9. The device of claim 8, wherein each element of the polarizing layer corresponds to an element of the second multi-element image sensor.   12. The device of claim 11, wherein the corresponding elements and elements of the polarizing layer and the second multi-element image sensor are registered with each other and with corresponding elements of the first multi-element image sensor.   The device of claim 1, wherein the polarizing layer comprises a reflective polarizer.   The device of claim 1, wherein the polarizing layer comprises an absorbing polarizer.   The device of claim 1, wherein the polarizing layer comprises a polarizing metal grating, a dielectric grating, or an air gap grating.   The device of claim 1, further comprising a color filter layer comprising an array of color filter elements. The device of claim 1,
An electronic processing module in communication with the device, wherein, in operation, the device detects incident light and sends a signal to the electronic processing module, wherein the electronic processing module performs, based on the signal, A system for determining information about the intensity of the incident light and information about the polarization of the incident light.   19. The information regarding the polarization of the incident light, the relative intensity of the incident light polarized in a first direction and the incident light polarized in a second direction orthogonal to the first direction. System.   18. The system of claim 17, wherein the information regarding intensity and polarization is determined for each of a plurality of locations across the device.   20. The system of claim 17, further comprising one or more optical elements positioned to focus the incident light onto the device.   21. The system of claim 20, wherein the one or more optical elements image light onto the device.   A camera comprising the system according to claim 17.   A spectral detector comprising the system according to claim 17.

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